New question - TC lockup on the E40D

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Nov 1, 2006 | 12:21 PM

93_E_350

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New question - TC lockup on the E40D

I have a question about the TC lockup on the E40D

I was looking at doing the toggle switch manual lock up of the TC on the E40D but then I found another wire that controls torque converter clutch coast solenoid and I think I would like to interrupt that instead that way my transmission will still work normally but not unlock when I back off on the go accelerator or coasting down hill. What do you think? Has anyone tried this yet?

Nov 1, 2006 | 04:52 PM

Hamberger

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From: Ladner, British Columbia

Can't say that I have tried it, looks interesting. Are you sure this solenoid is for the TC clutch? Why would there be two separate solenoids for the TC clutch control?

Seb.....

Nov 1, 2006 | 09:36 PM

93_E_350

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Hamberger,

I’m going to track down the wires tomorrow and do some testing. The good thing is it’s a van so the wire bundle comes right up the back of the engine so I can pop off the doghouse and have at it. I’m going to hook up a few test leads and see what the meter does on the coast clutch solenoid compared to the TC lock up solenoid…

I expecting a variation of the following:

At the speed of 55mph with the vehicle warm you should have a reading of about 0.5 to 3.0 volts. If you apply the brake (just a little) and hold the speed at 55 you should see the voltage jump to 12-14 volts. If you let off the gas the voltage should be 12-14 volts. As you release the brake and get back on the gas return to 55 and level out you should see the voltage drop again to 0.5-3.0 volts. With the vehicle in park the voltage should again be 12-14 volts. You will notice that when lockup engages the voltage drop occurs and lockup takes place.

I’m thinking that they are two different controls one works off speed reference (35 mph) and braking, and the other reacts to coasting or slack situations. When I back off on the accelerator or go down hill I am hoping to see a voltage change on the coast solenoid wire similar to the TC lock up. If I find out different I let you know that also…

93

Nov 2, 2006 | 01:45 PM

Hamberger

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From: Ladner, British Columbia

TC Lock-up

Sounds good, let me know what you find out and let me know what the colour of the wire is that controls the cluch solenoid.

I am still puzzled as to the need for two separate solenoids to control the TC lock-up.

Seb....

Nov 2, 2006 | 02:20 PM

Casey

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That should be really cool if you energize the coast clutch solenoid when in fourth gear. I don't know if you will instantly smoke the coast clutch or if you will lock up the rear wheels. One of those is going to happen.

The coast clutch CANNOT be on when the overdrive clutch is on. If they are both on it will try to stop the output shaft from turning RIGHT NOW. It should be REALLY exciting!

The coast clutch and the torque converter clutch are two separate clutches. That's why there are two separate solenoids.

Nov 2, 2006 | 02:46 PM

93_E_350

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Thanks for the input Casey!

I can do with out that kind of excitement!!!

I was doing a little more reading and it sounds like “when the OD” is off the coast solenoid kicks in and acts like and engine brake – possibly only 1<SUP>st</SUP> and 2<SUP>nd</SUP> gear?

What I was originally looking for was a way to hook up a led light to monitor the TC lock up and I ran across the coast solenoid…

Any further info would be appreciated!

93

Nov 2, 2006 | 07:58 PM

Casey

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You want to look at the torque converter clutch solenoid. Ignore the coast clutch solenoid. It won't tell you anything useful. It is used to provide engine braking in every gear except overdrive.